1. Field of the Invention
The present invention relates to a circuit-component supplying apparatus which supplies circuit components such as electric-circuit or electronic-circuit components, a circuit-component feeder which stores and supplies circuit components, and a circuit-component supplying method, and relates particularly to the art of improving the circuit-component supplying efficiency.
2. Related Art Statement
There is known a circuit-component supplying apparatus which includes a plurality of feeders each of which stores a number of circuit components, and which selects an appropriate one of the feeders so that the selected feeder feeds or supplies the components. More specifically described, the known circuit-component supplying apparatus includes (A) a plurality of feeders each of which stores a plurality of circuit components of a same sort and which supplies the components one by one from a component-supply portion thereof; (B) a movable table which holds the feeders such that the respective component-supply portions of the feeders are arranged along a line and which is movable in a direction parallel to the line; and (C) a table-driving device which moves and stops the movable table to position the component-supply portion of each of the feeders at a predetermined component-supplying position.
The movable table may be a linearly movable table to which a plurality of feeders are attached such that the respective component-supply portions of the feeders are arranged along a straight line and which is movable in a direction parallel to the straight line; or a full-circular table which is rotatable about a vertical axis line and to which a plurality of feeders are attached such that the respective component-supply portions of the feeders are arranged along a circle whose center rides on the axis line.
Each of the feeders includes a main portion and a circuit-component holding portion. For example, U.S. patent application Ser. No. 08/637,380, now U.S. Pat. No. 5,873,691 discloses a circuit-component supplying apparatus which includes a feeder including a main portion and additionally a reel-holding portion as a component-holding portion. In the disclosed apparatus, circuit components are given in the form of a tape, which is wound around a reel which is held by the reel-holding portion such that the reel is rotatable about an axis line thereof and is detachable from the reel-holding portion. The reel-holding portion is fixed to the main portion, and the tape is drawn out of the reel by a tape-feeding device provided in the main portion, so that the components carried on the tape are fed one by one to a component-supply portion of the feeder.
The main portion of each feeder is held by the movable table, so that the main portion is moved with the table as if it were an integral portion of the table. Thus, the main portion does not vibrate relative to the table. On the other hand, the component-holding portion may vibrate relative to the table. If the component-holding portion is sufficiently large, the vibration thereof will sufficiently decrease. However, the mass of each feeder will increase and, when the movable table holding those feeders is accelerated and decelerated, the vibration of the circuit-component supplying apparatus as a whole will increase.
Hence, the circuit-component supplying apparatus disclosed in the above-identified U.S. patent application employs a reel-holding-portion-vibration preventing device. The preventing device includes a bucket which is fixed to the movable table and in which the respective reel-holding portions of the feeders are accommodated, and two engagement members provided on the bucket. Each of the two engagement members has a plurality of engagement recesses each of which is engageable with a corresponding one of two engagement plates of each of the reel-holding portions. In the state in which the two engagement plates of each reel-holding portion are engaged with one of the engagement recesses of one of the two engagement members and a corresponding one of the engagement recesses of the other engagement member, respectively, the reel-holding portion is prevented from vibrating in the direction of width thereof, i.e., in the direction of movement of the movable table. In particular, one of the two engagement members is provided with a pressing device which presses one engagement plate of the reel-holding portion against one side surface of one engagement recess, so as to prevent the movement of the plate. Thus, the reel-holding portion does not need a high rigidity, for the purpose of being prevented from vibrating when the movable table is accelerated and decelerated. Therefore, the prior apparatus is free from the problem of failing to supply circuit components because the component-supply portion of each feeder is moved out of position due to the vibration of the main portion thereof resulting from the vibration of the reel-holding portion thereof.
In the above-mentioned prior apparatus, the total mass of the movable elements including the movable table and the plurality of feeders is less increased than in the case where each of the reel-holding portions has a high rigidity. However, since the prior apparatus employs the reel-holding-portion-vibration preventing device, the total mass of the movable elements is more or less increased. Therefore, if the acceleration and deceleration of the movable table are increased for improving the component supplying efficiency, the vibration of the supplying apparatus as a whole will be large, which leads to lowering the accuracy of positioning of each feeder and even causing each feeder to fail to supply a circuit component or components. In addition, since the total mass is high, the table-driving device should be one which has a large capacity or high performance, which leads to increasing the production cost of the supplying apparatus. On the other hand, if the movable table is moved at low acceleration and deceleration for improving the accuracy of positioning of each feeder and thereby improving the reliability of supplying of circuit components, the component supplying efficiency will be lowered.
It is therefore an object of the present invention to provide a circuit-component supplying apparatus which enjoys an improved circuit-component supplying efficiency or reliability.
It is another object of the present invention to provide a circuit-component feeder which enjoys an improved circuit-component supplying efficiency or reliability.
It is another object of the present invention to provide a circuit-component supplying method which enjoys an improved circuit-component supplying efficiency or reliability.
It is another object of the present invention to provide a circuit-component mounting system which enjoys an improved circuit-component mounting efficiency or reliability.
The present invention provides a circuit-component supplying apparatus, a circuit-component feeder, a circuit-component supplying method, and a circuit-component mounting system which have one or more of the technical features which are described below in respective paragraphs given parenthesized sequential numbers (1) to (30). Any technical feature which includes another technical feature shall do so by referring, at the beginning, to the parenthesized sequential number given to that technical feature. Thus, two or more of the following technical features may be combined, if appropriate. Each technical feature may be accompanied by a supplemental explanation, as needed.
(1) According to a first feature of the present invention, there is provided a circuit-component supplying apparatus comprising a plurality of feeders each of which stores a plurality of circuit components of a same sort and which supplies the components one by one from a component-supply portion thereof; a movable table which holds the feeders such that the respective component-supply portions of the feeders are arranged along a line and which is movable in a direction parallel to the line; and a table-driving device which moves and stops the movable table to position the component-supply portion of each of the feeders at a predetermined component-supplying position, the feeders comprising at least one connected feeder which comprises a main portion which is held by the movable table and which supports a feeding mechanism which feeds the circuit components one by one to the component-supply portion of the connected feeder, a component-holding portion which holds the circuit components and from which the components are fed to the main portion by the feeding mechanism, and a connecting device which connects the component-holding portion to the main portion such that the connecting device allows a center of gravity of the component-holding portion and the circuit components held thereby to be moved relative to the main portion in a direction substantially parallel to the line. It is not essentially required that the center of gravity of the component-holding portion and the circuit components held thereby be positioned below the main portion. For example, the center of gravity may be positioned beside or above the main portion. In addition, the plurality of feeders may comprise one or ones each of which includes a main portion and a reel-holding portion and supplies circuit components in the form of a tape; one or ones each of which arranges, by utilizing vibration, tilt, or air flow, circuit components stored in its casing, into an array, and feeds the components one by one to its component-supply portion; or one or more feeders of another or other sorts. The connecting device may be one, described later, which includes a connecting member and two hinge devices and which allows the whole of the component-holding portion to be substantially parallel-translated relative to the main portion. However, it is not limited to that. For example, the connecting device may be provided by an attachment portion of the component-holding portion which is attached to the main portion and which is formed of an elastically deformable material. In this case, too, the attachment portion allows the center of gravity of the component-holding portion and the circuit components to be moved relative to the main portion. That is, without any connecting device independent of the component-holding portion, the center of gravity of the component-holding portion and the components may be allowed to move relative to the main portion. The line along which the respective component-supply portions of the feeders are arranged may be a straight line, a circle, an arc (i.e., a part circle), a curve other than the arc, or any combination of two or more of those lines. If the line is a straight line, the movable table is a linearly movable table; if the line is a circle, the table is a circular (i.e., full-circular) table which is rotatable about an axis line; and if the line is an arc, the table is a sectorial table which is rotatable about an axis line. The circular or sectorial table can be said as a rotary table which is rotatable about an axis line. In the case where the movable table is the rotary table, the main portion of the connected feeder is held by the rotary table, and the main portion is rotated as if it were an integral portion of the table, when the table is rotated. However, the component-holding portion and the circuit components whose center of gravity is movable relative to the main portion in the direction of movement of the connected feeder do not have to be rotated as if they were integral portions of the table. More specifically described, since the connecting device connects the component-holding portion to the main portion, the component-holding portion and the components are also rotated when the main portion is rotated, but are delayed, because of their inertial mass, from the main portion. Thus, the component-holding portion and the components are rotated at an acceleration and deceleration which are lower than an acceleration and a deceleration at which the main portion is rotated. Therefore, the vibration generated by the present apparatus as a whole is small. On the other hand, if the component-holding portion and the components are rotated at the same acceleration and deceleration as those of the main portion, the vibration generated by the present apparatus would be large. Accordingly, in the present apparatus, the rotary table can be rotated at higher acceleration and deceleration to more rapidly position the component-supply portion of the connected feeder at the component-supplying position, if the present apparatus is allowed to vibrate at the same level as that at which the apparatus would vibrate when the component-holding portion and the components are rotated at the same acceleration and deceleration as those of the main portion. Thus, the present apparatus can improve its component-supplying efficiency. Alternatively, the present apparatus can reduce the vibration and thereby improve the accuracy of positioning of the connected feeder at the component-supplying position, without improving the component-supplying efficiency. In the latter case, the present apparatus can employ the table-driving device which has a small capacity, i.e., a low performance. The more the circuit components to be supplied are, and the larger the mass of the component-holding portion is, the more advantageous the present apparatus is. In the case where the movable tale is the linearly movable table, the component-holding portion and the circuit components are delayed, because of their inertial mass, from the main portion, when the table is moved along the straight line. Owing to the connecting device, the component-holding portion and the components are moved at an acceleration and deceleration which are lower than an acceleration and a deceleration at which the main portion is moved. Thus, the vibration generated by the present apparatus is small. In the case where the movable table is the circular table that produces, when being rotated, a moment about its axis line only, the vibration generated by the present apparatus as a whole is naturally smaller than that generated in the case where the linearly movable table is linearly moved. In addition, since the component-holding portion and the components are rotated at lower acceleration and deceleration than the circular table, the vibration generated by the apparatus is still smaller. Accordingly, the apparatus can still more improve its component-supplying efficiency. In the case where the movable table is the sectorial table which is rotatable about an axis line, like the circular table, but whose center of gravity does not ride on the axis line, unlike the circular table, the sectorial table have some natures similar to those of the linearly movable table. However, owing to the sectorial table, the present apparatus generates only smaller vibration as compared with an apparatus employing the linearly movable table. In addition, since the component-holding portion and the components are rotated at lower acceleration and deceleration than the sectorial table, the vibration generated by the apparatus is still smaller. Accordingly, the apparatus can still more improve its component-supplying efficiency.
(2) According to a second feature of the present invention which includes the first feature (1), the connecting device comprises means for connecting the component-holding portion of the connected feeder to the main portion thereof such that a whole of the component-holding portion is substantially parallel-translateable relative to the main portion in the direction substantially parallel to the line. In the present apparatus, the whole of the component-holding portion of the connected feeder is substantially parallel-translateable relative to the main portion thereof. In this case, the angle of inclination of the component-holding portion when the component-holding portion is delayed from the main portion is smaller (or zero) than that in the case where the component-holding portion is connected to the main portion such that the component-holding portion is pivotable relative to the main portion about an axis line.
(3) According to a third feature of the present invention which includes the first or second feature (1) or (2), the component-holding portion of the connected feeder comprises a reel-holding portion which holds a reel around which a tape carrying the circuit components is wound, and wherein the reel-holding portion is pendent from the main portion of the connected feeder such that a whole of the reel is positioned below the main portion. All of the feeders employed in the present apparatus may be ones each of which includes a main portion and a reel-holding portion, or only one or more (not all) of the feeders may be one or ones each of which includes a main portion and a reel-holding portion. In the latter case, one or more feeders other than the feeder or feeders each of which includes the main portion and the reel-holding portion may be, e.g., one or ones each of which arranges, by utilizing vibration, etc., circuit components stored in its casing, into an array, and feeds the components to its component-supply portion. All of the feeders each of which includes the main portion and the reel-holding portion may be pendent feeders each of which includes the main portion and the reel-holding portion pendent from the main portion, or only one or more (not all) of the feeders may be a pendent feeder or feeders. In the latter case, one or more feeders other than the pendent feeder or feeders may be, e.g., a known one or ones each of which includes a main portion and a reel-holding portion which is connected in series to one end portion of the main portion. The known feeder or feeders may be employed for supplying circuit components of a particular sort which is rarely supplied or which has a very small size, because the weight of its or their reel-holding portion or portions and the circuit components held thereby is low. In the case where the reel of the connected feeder is entirely located below the main portion of the feeder, at least a portion of the reel-holding portion of the feeder overlaps the main portion thereof in a component-feeding direction. Accordingly, the connected feeder may have, in the component-feeding direction, a dimension smaller than that of a known feeder whose main portion and reel-holding portion are connected to each other in series in that direction. Thus, the present apparatus can enjoy a high component-supplying efficiency. When a tape carrying circuit components has been completely consumed on a feeder, the reel of the feeder, or the feeder itself, should be replaced by another reel or feeder. To this end, the operation of the apparatus must be stopped. Accordingly, in recent years, it has been practiced to use a long tape for reducing the frequency of the replacing or stopping operations and thereby improving the component-supplying efficiency. However, the longer the tape is, the greater the size of the reel or the reel-holding portion should be. Thus, it is more difficult for feeders to be used with a circular table. As described above, in the known feeder, the component-supply portion thereof is provided by one of opposite end portions of the main portion thereof, and the reel-holding portion thereof is connected to the other end portion of the main portion. The known feeder must be mounted on the circular table, such that the component-supply portion thereof is located along the outer peripheral portion of the table and the reel-holding portion is located on the side of the axis line of rotation of the table. Accordingly, in order to mount, on a circular table, a feeder having a great reel-holding portion capable of holding a reel having a great diameter, the circular table should also have a great diameter. In addition, generally, the reel-holding portion has a greater width than that of the main portion. Since the feeders are mounted on the circular table having an annular shape such that the reel-holding portions of the feeders are located along the inner peripheral portion of the annular table, it is easy to provide a sufficient space between each pair of adjacent main portions, whereas it is difficult to provide a sufficient space between each pair of adjacent reel-holding portions. Thus, the maximum number of feeders that can be mounted on the circular table is limited to a small number. Accordingly, the frequency of the reel or feeder replacing operations cannot be reduced and the circuit-component supplying efficiency cannot be improved. An increased number of feeders can be mounted on a circular table having an increased diameter. In the last case, however, since the moment of inertia of the circular table and the feeders held thereby is increased, the acceleration and deceleration at which the table is rotated should be lowered for reducing the vibration produced thereby. Eventually, a longer time is needed for positioning each feeder, which leads to lowering the component supplying efficiency. In contrast, since the reel-holding portion of the connected feeder is pendent from the main portion such that the reel is entirely positioned below the main portion, the feeder can have a small dimension in the component-feeding direction. Therefore, the rotary table can hold a number of feeders without having to have a great diameter. Thus, the frequency of the reel or feeder replacing operations can be reduced, and the rotary table can be rotated at high acceleration and deceleration. That is, the present apparatus can enjoy a high component-supplying efficiency. In the case where the movable table is the linearly movable table that is linearly movable, the present apparatus can have a small dimension in a direction perpendicular to the direction of movement of the linearly movable table, because the feeder can have a small dimension in the component-feeding direction. Thus, the present apparatus occupies a small space only.
(4) According to a fourth feature of the present invention which includes any one of the first to third features (1) to (3), the feeders comprises a plurality of the connected feeders, and wherein the apparatus further comprises a component-holding-portion binder including a plurality of engaging portions which are engaged with the component-holding portions of the connected feeders, respectively, such that the component-holding-portion binder is substantially immovable relative to the component-holding portions in the direction substantially parallel to the line. The component-holding-portion binder may be one which simply binds the component-holding portions of the connected feeders with each other, is held by the component-holding portions, and prevents the component-holding portions from swinging independent of each other. However, as described later, the binder may be provided by a bucket which is attached by a binder attaching device to the movable table such that the bucket is movable relative to the table. In this case, the weight of the binder is supported by the movable table, and accordingly the component-holding portion of each connected feeder does not have to be strong enough to support the binder. Alternatively, at least a portion of the weight of the component-holding portion may be supported by the binder. In either case, the component-holding portion and/or the connecting device can be simplified. When the movable table is moved, the component-holding portions which are prevented by the binder from being moved relative to each other are delayed together with each other from the corresponding main portions. Thus, those component-holding portions are effectively prevented from individually moving relative to each other and thereby colliding with each other. Therefore, the generation of vibration and noise is prevented.
(5) According to a fifth feature of the present invention which includes the fourth feature (4), the circuit-component supplying apparatus further comprises a shock-absorbing following-causing device which causes the component-holding-portion binder to follow the movable table being moved, while absorbing a shock produced by the binder following the table. The shock-absorbing following-causing device allows the component-holding-portion binder to be delayed from the movable table and causes the binder to follow the table being moved, while reducing the vibration produced by the binder. Thus, the following-causing device causes the component-holding portions to follow the corresponding main portions. That is, the component-holding portions follow the corresponding main portions, while being delayed therefrom. The following-causing device causes the binder to follow the table, while preventing a great shock from being produced when the movement of the binder is started or stopped. Therefore, the component-holding portions can slowly and reliably follow the corresponding main portions, respectively.
(6) According to a sixth feature of the present invention which includes the fifth feature (5), the shock-absorbing following-causing device comprises a delay-allowing and returning device which allows, when the movable table is accelerated, the component-holding-portion binder to delay from a reference phase thereof relative to the table, and which returns, when the acceleration of the table continues to be zero, the binder to the reference phase thereof relative to the table. In the present apparatus, when the movable table is accelerated, the component-holding-portion binder is delayed with the component-holding portions, from the table, which leads to preventing a larger vibration which would be produced if the binder and the component-holding portions are moved at the same acceleration as that of the table. When the acceleration of the movable table continues to be zero in a state in which the table is stopped, or is moved at a constant speed, the binder is returned with the component-holding portions to its reference phase relative to the table.
(7) According to a seventh feature of the present invention which includes the sixth feature (6), the delay-allowing and returning device comprises a biasing device which biases, between the component-holding-portion binder and the movable table, the binder toward the reference phase thereof relative to the table; and a damping device which reduces a speed of the movement of the binder relative to the table. In the present apparatus, the component-holding-portion binder is returned to its reference phase relative to the movable table, by the biasing force of the biasing device. In addition, the damping device lowers the speed of movement of the binder relative to the table. Thus, the vibration of the binder relative to the table is effectively attenuated. The damping device may be one which lowers the speed of movement of the binder relative to the table when the binder is returned to its reference position relative to the table by the biasing force of the biasing device, as will be described in connection with the preferred embodiments of the invention; or one which lowers the speed of movement of the binder relative to the table when the table is accelerated and accordingly the binder is delayed from the table, as will be also described in connection with the embodiments of the invention. Moreover, in the case where the attenuating force of the damping device increases as the amount of delaying of the binder from the table increases, the damping device prevents the generation of a large shock and also functions as a stopping device which limits the amount of delaying of the binder from the table, i.e., defines the maximum delaying amount of the binder from the table. All those advantages are possessed by the preferred embodiments of the invention, described later, wherein the damping effect and the delaying-amount limiting effect, in particular, are exhibited irrespective of in which direction the table is rotated.
(8) According to an eighth feature of the present invention which includes any one of the fourth to seventh features (4) to (7), the component-holding-portion binder comprises a bucket which opens upward and which accommodates the respective component-holding portions of the connected feeders. In this case, the component-holding portions of the connected feeders are protected by the bucket and are prevented from being interfered with by the other elements.
(9) According to a ninth feature of the present invention which includes any one of the first to eighth features (1) to (8), the connecting device comprises at least one connecting member which extends in a direction substantially perpendicular to a direction in which the movable table is moved by the table-driving device; a first hinge device which connects one of opposite end portions of the connecting member to the main portion of the connected feeder, such that the connecting member is pivotable about a first axis line which is perpendicular to the direction of movement of the movable table; and a second hinge device which connects the other end portion of the connecting member to the component-holding portion of the connected feeder, such that the connecting member is pivotable about a second axis line which is perpendicular to the direction of movement of the movable table and which is distant from the first axis line in the direction substantially perpendicular to the direction of movement of the movable table. The connecting device may be provided by an elastic or flexible member. In this case, the elastic deformation of the elastic member allows the relative movement of the main portion and the component-holding portion. However, the elastic member has the problem of fatigue failure. In contrast, the connecting device in accordance with the ninth feature (9) is free from that problem. This connecting device has another advantage that when the respective component-holding portions of a plurality of connected feeders are delayed from the corresponding main portions, each pair of adjacent component-holding portions are prevented from being moved relative to each other in a direction parallel to the side surfaces of the component-holding portions.
(10) According to a tenth feature of the present invention which includes any one of the sixth to ninth features (6) to (9), the delay-allowing and returning device comprises at least one connecting member which extends in a direction substantially perpendicular to a direction in which the movable table is moved by the table-driving device; a first hinge device which connects one of opposite end portions of the connecting member to the movable table, such that the connecting member is pivotable about a first axis line which is perpendicular to the direction of movement of the movable table; and a second hinge device which connects the other end portion of the connecting member to the component-holding-portion holder, such that the connecting member is pivotable about a second axis line which is perpendicular to the direction of movement of the movable table and which is distant from the first axis line in the direction substantially perpendicular to the direction of movement of the movable table. When the movable table is moved, the pivotal movement of the connecting member allows the component-holding-portion binder to be delayed from the table, so that the binder is slightly moved up, like a pendulum, by the pivotal movement of the connecting member. Thus, the binder stores a potential energy, which provides a force to return the binder to its reference phase relative to the table. Accordingly, without any biasing device or any damping device, the delay-allowing and returning device permits the binder to delay from the table and causes the binder to follow the table at a lower acceleration. Therefore, it is not essentially needed to employ both the first combination of the connecting member and the hinge devices, and the second combination of the biasing device and the damping device, though all of them are employed in the embodiments of the invention which will be described later. The delay-allowing and returning device also functions as a binder attaching (or connecting) device which attaches (or connects) the binder to the table. The delay-allowing and returning device may, or may not, be used with the delay-allowing and returning device in accordance with the seventh feature (7), or vice versa. The delay-allowing and returning device is particularly advantageous when it is used with the pendent feeder including the connecting means in accordance with the ninth feature (9). In this case, when the movable table is moved, the component-holding portion of the feeder and the component-holding-portion binder behave like each other, with respect to both the direction of movement of the feeder and the vertical direction, so that the relative movement of the component-holding portion and the binder is reduced. In a particular case where the connecting member of the delay-allowing and returning device has the same length as that of the connecting member of the connecting device of the feeder, the component-holding portion and the binder behave in the same manner, so that the relative movement of the component-holding portion and the binder is zeroed. The present circuit-component supplying apparatus may employ an exclusive binder attaching (or connecting) device, in addition to the delay-allowing and returning device. For example, the exclusive binder attaching device may be provided by a pair of guide members which extend along a line parallel to the direction of movement of the movable table and which are engaged with each other such that the two guide members are movable relative to each other in a direction parallel to the line. One of the two guide members is fixed to the binder, and the other guide member is fixed to the table. The pair of guide members has the function of allowing the binder to be delayed from the table, but does not have the function of returning the binder to its reference phase relative to the table. Accordingly, a biasing device as a sort of returning device is employed for returning the binder to its reference phase. In addition, a damping device may be employed for lowering the speed of movement of the binder when it is returned to its reference phase.
(11) According to an eleventh feature of the present invention which includes any one of the first to tenth features (1) to (10), the main portion of the connected feeder is elongate in a substantially horizontal direction perpendicular to a direction in which the movable table is moved by the table-driving device, and the connected feeder comprises a pendent feeder whose component-holding portion is pendent from an intermediate portion of the elongate main portion thereof. In this case, the main portion of the pendent feeder can have, in the component-feeding direction, a dimension which is reduced by the dimension of the component-holding portion in the same direction. Thus, the present feeder enjoys a compact construction, which contributes to improving the degree of freedom of designing of various peripheral devices of the present apparatus.
(12) According to a twelfth feature of the present invention which includes the eleventh feature (11), the main portion of the pendent feeder includes a held portion which is located on one side of the intermediate portion thereof and which is held by the movable table.
(13) According to a thirteenth feature of the present invention which includes the twelfth feature (12), the main portion of the pendent feeder includes the component-supply portion thereof which is located on the other side of the intermediate portion of the main portion and is distant from the held portion of the main portion.
(14) According to a fourteenth feature of the present invention which includes any one of the first to thirteenth features (1) to (13), the movable table comprises a rotary table which is rotatable about a first axis line which is substantially vertical. The rotary table may be a circular table or a sectorial table. The main portion of the connected feeder may be held by the rotary table such that the component-supply portion of the feeder is distant from, or near to, the first axis line, depending upon the manner in which the circuit component are picked up from the feeder. In the case where the movable table is the rotary table, the present apparatus can have a more compact construction than in the case where the movable table is the linearly movable table. An apparatus employing the linearly movable table needs, in addition to a space which is occupied by the table, a space in which the table is moved. Thus, the linear-type apparatus needs at least two times as much space as that needed by the rotary-type apparatus. In addition, it can be generally said that when the rotary table is rotated, the table generates only the momentum about the axis line of rotation thereof. Therefore, the rotary-type apparatus produces less vibration than the linear-type apparatus. Accordingly, the vibration of the floor on which the rotary-type apparatus is placed is reduced, which leads to preventing operators working on the floor from feeling discomfort and which leads to preventing other apparatuses placed on the same floor, from suffering problems which would otherwise be caused by the vibration, for example, lowered accuracy of positioning of a movable member.
(15) According to a fifteenth feature of the present invention which includes the fourteenth feature (14), the main portion of the connected feeder is elongate in a substantially horizontal direction perpendicular to a direction in which the movable table is moved by the table-driving device, and wherein the main portion includes a held portion which is nearer to the first axis line than the component-supply portion thereof and which is held by the movable table. In this case, the circuit components are supplied from the component-supply portion located distant from the first axis line.
(16) According to a sixteenth feature of the present invention which includes the fourteenth or fifteenth feature (14) or (15), the connecting device comprises relative-rotation allowing means for allowing the component-holding portion of the connected feeder to be rotated relative to the main portion thereof about a second axis line parallel to the first axis line. The connected feeder is held by the rotary table which is rotatable about the first axis line and, when the table is rotated and accordingly the component-holding portion is moved relative to the main portion, a small difference is produced between the angular or rotation position of the component-holding portion and that of the main portion about the first axis line. This difference increases in an radially outward direction from the first axis line. The relative-rotation allowing means allows the generation of this difference, thereby preventing the connecting device from being damaged.
(17) According to a seventeenth feature of the present invention which includes any one of the fourteenth to sixteenth features (14) to (16), the movable table comprises a rotary table which is rotatable about a first axis line which is substantially vertical, and at least one of the connecting member and the first and second hinge devices of the delay-allowing and returning device comprises relative-rotation allowing means for allowing the component-holding-portion binder to be rotated relative to the rotary table, about a second axis line of the connecting member parallel to the first axis line, when the binder is rotated relative to the table about the first axis line. Since the binder is attached to the table, a small difference is produced between the rotation position of the binder and that of the table. However, the relative-rotation allowing means allows this difference, thereby preventing the connecting member from being damaged. Even if the binder may not be attached to the table, a small difference is produced between the rotation position of the binder and that of the main portions of the feeders. Hence, it is preferable to employ relative-rotation allowing means for allowing the generation of the difference.
(18) According to an eighteenth feature of the present invention which includes the seventeenth feature (17), the connecting member comprises a torsion member which is elastically twistable about an axis line thereof as the second axis line, and which allows the component-holding portion of the connected feeder to be rotated relative to the main portion thereof about the second axis line. In the case where the connecting device of the connected feeder comprises the connecting member and the two hinge devices as described above, that connecting member may be likewise provided by a torsion member which is elastically twistable about an axis line thereof parallel to the first axis line, and which provides relative-rotation allowing means for allowing the component-holding portion to be rotated relative to the main portion.
(19) According to a nineteenth feature of the present invention which includes any one of the first to eighteenth features (1) to (18), the connecting device comprises means for connecting the component-holding portion of the connected feeder to the main portion thereof such that the component-holding portion is pivotable relative to the main portion about an axis line perpendicular to a direction in which the movable table is moved by the table-driving device. In the present apparatus, when the rotary table is rotated and accordingly the main portion of the connected feeder is moved, the component-holding portion of the feeder feeder is rotated relative to the main portion, so that the component-holding portion is delayed from the main portion. This contributes to reducing the vibration of the present apparatus as a whole. Since the component-holding portion is connected to the main portion such that the component-holding portion is pivotable about the single, second axis line, the connecting device enjoys a simple construction. In the present apparatus, too, it is preferable to employ a component-holding portion binder which binds the respective component-holding-portions of a plurality of connected feeders with each other, so that the component-holding portions are prevented from swinging independent of each other. However, in the present apparatus, when the component-holding portions are delayed from the main portions, each pair of adjacent component-holding portions are moved relative to each other in a direction parallel to the side surfaces of those component-holding portions. Therefore, the component-holding portion binder should be one which can bind the component-holding portions while allowing each pair of adjacent component-holding portions to be moved relative to each other in the direction parallel to the side surfaces thereof. For example, the binder may be provided by a highly flexible member formed of rubber or the like. In addition, it is possible to cover each of the respective contact (i.e., side) surfaces of the component-holding portions with a cover member (e.g., a rubber member) having a friction coefficient higher than at least that of the material of the component-holding portions. In this modified form, the swinging (vibration) of the component-holding portions is effectively attenuated because of the friction between each pair of adjacent cover members. The component-holding-portion binder may be omitted, and each of the contact surfaces of the component-holding portions may be provided with a cushion member for reducing the noise generated when each pair of adjacent component-holding portions collide with each other. In the case where the cushion members have a high friction coefficient, those cushion members exhibit the effect of attenuating the swinging of the component-holding portions.
(20) According to a twentieth feature of the present invention, there is provided a feeder for storing a plurality of circuit components of a same sort and supplying the components one by one from a component-supply portion thereof, the feeder comprising a main portion which is adapted to be held by a movable table and which supports a feeding mechanism which feeds the circuit components one by one to the component-supply portion; a component-holding portion which holds the circuit components and from which the components are fed to the main portion by the feeding mechanism; and a connecting device which connects the component-holding portion to the main portion such that the connecting device allows a center of gravity of the component-holding portion and the circuit components held thereby to be moved relative to the main portion in a direction substantially parallel to a direction in which the movable table is moved. The present feeder is held by the movable table and, when the component-supply portion of the feeder is positioned at a component-supplying position by the movement and stopping of the table, the component-holding portion and the circuit components are delayed from the main portion, like the connected feeder employed in the circuit-component supplying apparatus in accordance with the first feature (1). Thus, the component-holding portion and the circuit components follow the main portion, at an acceleration and a deceleration lower than an acceleration and a deceleration of the main portion, respectively. Thus, the present feeder contributes to reducing the vibration generated by a circuit-component supplying apparatus, and thereby improving the circuit-component supplying efficiency or reliability of the apparatus.
(21) According to a twenty-first feature of the present invention which includes the twentieth feature (20), the main portion is elongate in a direction parallel to a direction in which the circuit components are fed by the feeding mechanism, and the component-holding portion is pendent from an intermediate portion of the elongate main portion.
(22) According to a twenty-second feature of the present invention which includes the twenty-first feature (21), the main portion includes a held portion which is located on one side of the intermediate portion thereof and which is adapted to be held by the movable table.
(23) According to a twenty-third feature of the present invention which includes the twenty-second feature (22), the main portion includes the component-supply portion which is located on the other side of the intermediate portion of the main portion and is distant from the held portion of the main portion.
(24) According to a twenty-fourth feature of the present invention which includes any one of the twentieth to twenty-third feature (20) to (23), the connecting device comprises relative-rotation allowing means for allowing the component-holding portion to be rotated relative to the main portion about an axis line which is substantially vertical.
(25) According to a twenty-fifth feature of the present invention which includes any one of the twentieth to twenty-fourth feature (20) to (24), the connecting device comprises at least one connecting member which extends in a direction substantially perpendicular to a direction in which the movable table is moved; a first hinge device which connects one of opposite end portions of the connecting member to the main portion, such that the connecting member is pivotable about a first axis line which is perpendicular to the direction of movement of the movable table; and a second hinge device which connects the other end portion of the connecting member to the component-holding portion, such that the connecting member is pivotable about a second axis line which is perpendicular to the direction of movement of the movable table and which is distant from the first axis line in the direction substantially perpendicular to the direction of movement of the movable table. The connecting member is pivotable about the second axis line relative to the main portion of the feeder, and is pivotable about the third axis line relative to the reel-holding portion of the same feeder. Thus, the connecting member allows the component-holding portion to be parallel translated relative to the main portion. Meanwhile, the connecting device may be provided by an elastic or flexible member (e.g., a leaf spring positioned in a plane perpendicular to the direction of movement of the table) which extends in the direction substantially perpendicular to the direction of movement of the table. In this case, the elastic deformation of the elastic member allows the relative movement of the main portion and the component-holding portion. However, the elastic member has the problem of fatigue failure. In contrast, this connecting device is free from that problem.
(26) According to a twenty-sixth feature of the present invention which includes the twenty-fifth feature (25), the connecting member comprises a torsion member which is elastically twistable about a lengthwise axis line thereof, and which allows the component-holding portion to be rotated relative to the main portion about an axis line which is substantially vertical.
(27) According to a twenty-seventh feature of the present invention, there is provided a method of supplying circuit components, comprising the steps of moving a movable table along a line, the movable table holding a plurality of feeders such that respective component-supply portions of the feeders are arranged along the line, each of the feeders storing a plurality of circuit components of a same sort and supplying the components one by one from the component-supply portion thereof, at least one of the feeders comprising a main portion which is held by the movable table and which supports a feeding mechanism which feeds the circuit components one by one to the component-supply portion thereof, and a component-holding portion which holds the circuit components and from which the components are fed to the main portion by the feeding mechanism, wherein a center of gravity of the component-holding portion and the circuit components held thereby is movable relative to the main portion in a direction substantially parallel to a direction in which the main portion is moved by the movement of the movable table, and intermittently stopping the movable table and thereby sequentially positioning the component-supply portion of each of the feeders at a predetermined component-supplying position where the each feeder supplies at least one circuit component from the component-supply portion thereof, wherein when the movable table is moved, the component-holding portion and the circuit components are moved at an acceleration and a deceleration which are lower than an acceleration and a deceleration, respectively, at which the main portion is moved. The explanations made in connection with the circuit-component supplying apparatus in accordance with the first feature (1) are also true with the present circuit-component supplying method. In short, the present method assures that circuit components are supplied with high efficiency and/or with high reliability. The present circuit-component supplying method may employ one or more of the first to nineteenth features (1) to (19) of the circuit-component supplying apparatus.
(28) According to a twenty-eighth feature of the present invention, there is provided a circuit-component mounting system comprising the circuit-component supplying apparatus in accordance with the first feature (1); a circuit-substrate supporting device which supports a circuit substrate; and a circuit-component mounting device which receives the circuit components supplied by the circuit-component supplying apparatus and mounts the components on the circuit substrate supported by the circuit-substrate supporting device. The present system is very advantageous if it employs the circuit-component mounting device in accordance with the twenty-ninth feature (29) described below. However, the present system may employ a circuit-component mounting device of a type which includes one or more component-mounting heads and a movable member which supports the component-mounting head or heads and which is movable to any desired position in one direction, or in each of two directions perpendicular to each other, in a horizontal plane. The latter mounting device may also be so required, for the purpose of, e.g., improving its component-mounting efficiency, that the or each mounting head be able to receive the components at a predetermined position. In particular, in the case where the latter mounting device is provided by the former mounting device of a type wherein the head-revolving device thereof is supported on a movable member which is movable to any desired position in one direction, or in each of two directions perpendicular to each other, in a horizontal plane, it is preferred that each of the component-mounting or -holding heads be able to receive circuit components at a predetermined position.
(29) According to a twenty-ninth feature of the present invention which includes the twenty-eighth feature (28), the circuit-component mounting device comprises a plurality of component-holding heads which are revolveable about an axis line which is inclined with respect to a horizontal plane, and a head-revolving device which revolves the component-holding heads about the axis line and sequentially stops the heads at a predetermined component-mounting position, and wherein the circuit-substrate supporting device comprises a circuit-substrate supporting member which supports the circuit substrate, and a supporting-member moving device which moves the circuit-substrate supporting member to a desired position on a substantially horizontal plane. The head-revolving device may be one which includes (a) a plurality of rotary members which supports the plurality of component-holding heads, respectively, and which are rotatable about a common axis line, and (b) a rotation-causing device which causes the rotary members to rotate about the common axis line in such a manner that each of the rotary members is stopped at least one time during its full (360 degrees) rotation and such that a predetermined time difference is maintained between each pair of angularly adjacent rotary members. This head-revolving device will be described in connection with the preferred embodiments of the invention. Alternatively, the head-revolving device may be one which includes (a) an intermittent-rotation body which is intermittently rotatable about an axis line and which supports the plurality of component-holding heads such that the heads are equiangularly spaced from each other about the axis line, and (b) a driving device which intermittently rotates the rotation body. In the latter case, the driving device may be one which can intermittently rotate the rotation body by a predetermined angular pitch in a predetermined direction, or one which can rotate and stop the rotation body by any desired angle in any desired direction. Moreover, in the case where the plurality of component-holding heads are supported on a rotatable body which is rotatable about an axis line, the central angle contained by one pair of angularly adjacent heads may be different from that of another or other pairs of adjacent heads.
(30) According to a thirtieth feature of the present invention which includes the twenty-eighth or twenty-ninth feature (28) or (29), the component-holding portion of the connected feeder comprises a reel-holding portion which holds, at a position below the circuit-substrate supporting device, a reel around which a tape carrying the circuit components is wound. The circuit-substrate supporting device is disposed at a height position suitable for the mounting of components in relation with the component mounting device. Thus, a vacant space may be left under the supporting device, and the reel-holding portion of the connected feeder may be positioned in that space. That is, a portion of the component supplying device may overlap the substrate supporting device in a horizontal direction. Thus, the present system enjoys a compact construction. In the case where the main portion of the connected feeder is held at a position higher than that of the circuit-substrate supporting device and, when the components are mounted, the circuit substrate is moved into a space between the main portion and the reel-holding portion, as will be described in connection with the embodiments of the invention, the circuit-component mounting system enjoys a more compact construction.